A large fumarole inside the Papandayan crater emitting large quantities of gas. Copyrighted photo by Nick Varley.
Papandayan is a stratovolcano which is found in a row of volcanoes. It has very distinctive yellow crater walls due to coloring by sulfur. The crater is surrounded by forest and extends to the northwest by a long, steep chasm. This chasm becomes a river channel at the foot of the mountain.
The highest part of the crater floor lies to the southeast. It is ~6600 feet (2000 m) high and sits ~800 feet (240 m) below the crater rim. The floor of this crater contains sulfurous pools of standing water, fumaroles, solfataras, mud volcanoes and hot springs. All this minor volcanic activity makes it quite noisy on the crater floor. A river which flows across the floor of the crater begins as a clear stream in the forest but quickly becomes heated and filled with sulfuric acid as it flows across the floor. The mud volcanoes on the floor of the crater are normally 2-4 feet (0.6-1.2 m) high and explode with great force. They eject hot, muddy water every 20-25 seconds.
Papandayan has had three eruptions in historic times. The last was in 1942.
Sources of Information:
Junghuhn, F., "Java, Its Shape, Covering, and Internal Structure: Part 2," p. 109-112, 1853.
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